This invention relates generally to the field of diving suits, and more particularly to improvements in sealing the wrist and neck openings thereof against the intrusion of water.
Diving suits are available in a wide variety and include so called wet suits and dry suits. In the former the suits are generally made to be close fitting and of thermally insulating material so that any water between the suit and the wearer's body is only a thin layer. The wet suit, once flooded, does not exchange much water and so is fairly effective at retaining body heat when used in water of moderate temperatures.
Diving and working in extremely cold water, however, calls for more stringent measures in conservation of body heat than is generally afforded by wet suits. Accordingly, under those circumstances a relatively loosely fitting, substantially watertight, dry suit is preferred that accommodates the use of thermally protective insulating underwear, which may also incorporate electrical, hot water, or chemical heating means.
Some dry suits have gloves or mittens integrally formed on the sleeves, and are designed so that the upper portion of the suit is directly connected, as by suitable clamp means, to a diving helmet. While those suits are notably effective in remaining internally dry, except for moisture condensing from the breathing gas, perspiration moisture, and the like, they are not readily used with hooded diving helmets or masks of the type that are not clamped directly to the suit. The integral gloves or mittens have often been ill fitting and cumbersome. Moreover, a tear or cut in the glove, which is likely to happen in working situations, results in substantial flooding of the suit.
U.S. Pat. Nos. 2,888,011; 3,351,056; 3,353,534; 3,534,408; and 3,958,275 are examples of helmet seals between the helmet and the neck or between the helmet and the suit, but do not disclose any seal between the suit and the neck of the diver that will prevent water entry to a suit while using a non-suit connected helmet or hooded mask. U.S. Pat. No. 3,493,972 discloses a waterproof suit having a continuous elastic seal about the neck and "conventional" wrist seals. Conventional wrist seals on diving suits have generally constituted tubular, thin-walled elastic rubber cuffs that grip the wrist of the diver after he forces his hand through. Other wrist and neck seals have comprised an in-turned or reentrant elastic cuff in an effort to exclude water.
Neck and wrist seals that rely on tight elastic bands or cuffs tend to restrict the diver's circulation of blood, or if not so tight as to inhibit circulation are prone to leak, especially with active movements during work.